Automobile transmission mechanism



Jan. 31, 1928.

W. C. SMITH AUTOMOBILE TRANSMISSION MECHANISM Filed March 2, 1927 5 Sheets-Sheet l M4 f M iii W. C. SMITH AUTOMOBILE TRANSMISSION MECHANISM 5 sheets-sheet 2 Filed March 2, 1927 Jan. 31, 1928.

' W. C. SMITH AUTOMOBILE TRANSMISSION MEcHAmsM 5 Sheets-Sheet 3 Filed March 2, 1927 Jan. 31, i928.

W. C. SMITH AUTOMOBILE TRANSMISSION MEGHANISM Filed March 2, 192'? 5 Sheets-Sheet 4 Jan. 31, 1928, 1,658,021

w. c. SMITH AUTOMOBILE TRANSMISSION MEGHANI SM Filed March 2, 1927 5 Sheets-Sheet 5 Patented Jan. 31, i928.

l .unirse arri: PATENT oFFIcE.

i WILLIAM C. SMITH, GF CHICAGO, ILLINOIS.

AUTOMOBlIiE TRLTANSMISSIN MECHANISM.

" means in operative relation with the pedal adaptedto 'engage' the disc faces for arrest ing the sun gear when the pedal is de'.- pressed by the operator; whereby a speed is obtained by double irictioiial resistance and asingle movement on the part of the operator without transverse `stresses in the mechanism. It is well lnown, in drum and'brake band construction for sun gee-.r arresting purposes, thatthe resultant of the tangential pulloi the band in two directions is a radial or` transverse stress which throws the gears out oi even mesh, causing gear noise and vibration; and that this stress produces internal friction, or a braking `action on the bearings within the drum, which detracts` from the amount ot` power which otherwise would be available. And, brake bands offering but a single :tiict-ional resistance require high pressure which causes rapid wear and frequent renewals.

A further object is to provide an automobile transmission mechanism. haa/ing `a pair of sun gears, with operative mechanism for rictionally arresting each` gear, automatically locliingthe gears together, unlocking the gears, and` compelling the gears to remain normally unlocked for tree idle rotation.

4And further objects are, iirst, to provide a seltengaging disc clutch tor automatically locking-sun gears together; second, to provide balanced clutch disengaging means tor unlocking the sun` gears ont suoli consti-ue tion as to exert equal pressures in opposite directions on clutch `clamping elements against `clutch. --spring resistance, whereby engine end thrust resulting in irictional loss and crank shaft bearing wear is prevented; third, to provideautomati c retaining means co-operating with the clutch disengaging means tor holding the clutch normally dis engaged and compelling the sun gears to reappiication ined March a, 192'?.` .serial No. i72g073.

main normally unlocked for tree idle rotation; fourth, to provide an engine accelerator pedal adapted to move the retaining means to inoperative position, whereby automaticclutch engagement is permitted; .tilt-h,

`to provide a normally neutral clutch clampingeleineiit capable not oniy of engaging the clutch for high speed, but also ot engaging arresting means for low speed; sixth, to provide clutch adjusting means ot such eonstruction that the clutch springs loclethe adjustment; seventh, to provide a pawl capable oil' locking the car, or the low speed when desired; and eighth, to provide a service brake pedal and a reverse speed pedal 'suitable for emergency braking purposes.

y l attain these objects by the mechanism illustrated inthe accompanying drawings,

in which 1 is substantially a vertical section oi the mechanism showing operating parts iii neutral position. Figs. 2 and 3 are, respectively, side and rear elevations ot the mechanism. Figs. 4, 5 and 6 are transverse sections of: parts of the mechanism on'corresponding lines,Fig. 1. Fig. 7 is a sectional view of control parts on` line 7 7, Fig. 2. Fig. 8 is a plan section of a. pedal bracket on line 8 8, Fig. 2. Fig. Qiis a vertical section of a partici1 the mechanism on line 9-9, Fig.`2. Fig. `10 is a sectional `view of a part of the mechanism on line `1O--1O, Fig. 3. vertical sections of modilied forms of mech- And, Figs. 11 and 12 are anism. .v `A forni oi" construction` as shown in Figs.

-1`to`10, inclusive, comprises planetary gear sets rotatably mounted onshafts 1 of an engine ily wheel 2. Each gear set includes gears 3 and a meshing with low and reverse .speed sun `gears 5 and 6, respectively, and a gear 7 meshing with a gear 8 iixed to rotate with a transmission shaft 9 which is journaled at one end in ily wheel 2 and at the other iii a two-part `housing 10 secured toa housing 11. i

A reverse speed disc 12 and clutch discs 13 are riXedto rotate with gear 6 through the medium ot a gear extension 14 to which the discs are splined. Frictional arresting means for disc 12 include a normally stationary abutment 15 and a plate C splined thereto. An operative relation Vbetween abutment 15, plate C, and a reverse speed pedal 17'is `formed by-apedal cam. sha-ft 18 whiclnis interposed. between said plate and a housing lia-nge 19, the cam shaft being adapted to rock on the flange and plate for pressing the plate against the disc and the disc against the abutment, in order to arrest the disc and gear 6. Cam shaft 18 projects through housing 10 and is held in position by a retaining screw 20, a clearance aperture 21 being indicated by dotted lines in Fig. 3.

A clutch clamping element 22 is secured to gear 5 and splined to a member B of a clutch clamping element 23 which is sleeved to element 22, these elements being spring-pressed in opposite directions by means of clutch springs 24. Element 23 includes clamping discs 25 splined to member B, and these clamping discs together with element 22 and member B are adapted to clamp discs 13 automatically for locking gears 5 and 6 together. Y

Alow speed disc 26 is fixed to rotate with gear 5 through the medium of element 22 and member B to which the disc is splined. Frictional arresting means for disc 26 include a normally stationary abutment 27 and a disc abutment 28 splined thereto. An operative .relation'between abutments 27 and 28 and a clutch pedal 29 is formed by element 23, including member B, and parts of clutch`disengaging means described hereinafter, said member being adapted to abut disc abutment 28 and press the same against disc 26 and disc26 against abutment 2'? for arresting itself7 disc 26 and gear 5. Element 23 includes a ball thrust bearing 30, and

Velement 22 includes a similar bearing 3l held in operative position by means of retaining collars 32 and 33.

Clutch disengaging means for unlocking gears 5 and 6 include parallel laterally eX- tending cam shafts 34 interposed between bearings 30 and 3l equi-distant from the centers thereof and adapted to rock on lateral faces of said bearings as well as on a flat surface 35 parallel to said faces formed in housing` 10, said shafts projecting through clearance apertures 36 in said housing and being provided at their inner ends with holes 37 for the reception of retaining screws 38. Cam shafts 34 have long rocking contacts which coincide with chords of the circular bearing faces. The pressures exerted on the bearings are equal and opposite in direction, reaction on bearing 3l being equal and opposite to the pressure required to move bearing 30 forwardly for clutch disengagement. Clutch pedal 29 having downward eXtensions 39is ,piv-oted to a shaft 40 mounted in a bracket 41 integral with housing l0, and a brake pedal` 42 adapted to be connected to aV brake in the usual manner is also pivoted to said shaft. An equalizer 43 pivoted to a pin 44 in extensions 39 is provided with headed pins 45 .seating on adjusting washers 46 and bearing against the free ends 'of cam shafta'rms 47 for rocking the cani shafts in opposite directions.

neaoai the other end of said shaft is adapted tol raise pawl A out of the path of tooth 48 for permitting clutch engagement. A gravityoperated pawl 59 swiveled to footboard 52 and projecting through an opening 58 therein is adapted when actuated by the operator to engage ratchet teeth 59 on pedal 29 and l hold the pedal in depressed low speed position for locking the low speed when the engine is ruiming. or the car when the engine is dead.

in operation` when pedal 29 is depressed, low speed is obtained, the pedal returning to neutral position by the action of the clutch springs upon release of pressure. For low speed and change to high speed, pedal 29 first depressed then the accelerator pedal to permit rearward movement of pedal past neutral to high speed position upon release of pressure. To stop the car, pressure on the brake pedal only is required after pedal 29 has been depressed'to or beyond neutral position. For reverse speed, pedal l? only is depressed, this pedal also serving for emergency braking purposes.

Clutch adjusting means include a screwthreaded connection GO between member B of element and the spring-pressed portion thereof, recesses 6l in element 22, one or more holes 62 in element 23 registering` with said recesses, and a normally closed opening 63 in housing l0. To adjust thc clutch, a suitable pry is employed for turning element 22 and member B relative to the springpressed portion of element 29.` an edge of a hole 62 serving as a fulcrum for the prying action. To alleviate friction during the turning movement, a washer 64 is interposed between springs 24 and element 23. Said springs lock the adjustment.

Adjusting means for abutmcnts l5 and 2T include screw-threaded connections (35 between the abutments and housing l0, Peripheral notches 67 are provided for cooperation with a suitable tool for turning the abutments to effect the desired adjustment, and larger notches 63 are also provided for engagement with a locking lug G9 removably secured in housing l0.

The modified form of mechanism shown in Fig. 1l includes plain clutch discs` and disc abutments 7l splined to abutment l5.

nesaoai And, the form shown inlTig..A 12 includes a single disc or plate clutch,.me1nber B being adapted to have direct `engagement with abutment 27. Y 1

For clearnessot description, itis `understood that :trictional ring lacings shown tor discs and other parts torm a partthereot, although in practice these ring lacings may be loosely interposed between the discs or parts. And, thediscs shown in Fig. ll, althoughplain, have lateral friction faces.

Frictional ,loss is not only prevented by the arresting discs but by the balanced clutch disengaging means, which cooperate inthe savingol powerduring low and reverse speed intervals when maximum power isrequired. And, since there is no lost motion ol' pedali 29 due to engine crank shalt bearing wear, the pedal may have a high leverage withconsequentease ol operation. It will `be noted that neutral positioning vol: parts requires no attentionon the part ol the operator, since 4pawl A is self-engaging by means ot a spring 72 on shalt 50 and raised out ol engaging position when the ac- Celera-tor pedal is depressed to accelerate the car speed betorechanging to high speed.

What I claim is:

l. An automobile transmission` mechanism comprising` in combination, af transmission shalt and a driven gear fixed thereto, a sun gear surrounding said shalt, ali-engine liy wheel, a shalt projecting from said lly wheel and a planetary gear set rotatably mounted thereomsaid gear setcomprising adriving gear in constant mesh with said drivengear and a `gear in constant mesh with said sun gear, an annular disc lined to rotate with said sun A(fear but l'reey to move axially relative thereto, lrictional arresting means adj acent one lateral lace ol said disc, a control pedal, and a second trictional arresting means in operative relation with said pedal adjacent the other laterallace of said disc, the construction being such that each Jfrictional means is compelled to engage its respective disc lace tor arresting the disc when the pedal is depressed by the operator.

2. An automobile transmission mechanism comprising in combination, a transmission shalt and a gear lined to rotate therewith, a sun gear, planetary gears meshing with said gears, an axially movable element having a lriction face fixed to rotate with the sun gear, an arresting abutment adjacent said lace, a housing` having a transverse surface, cam shafts adapted to Vroclr on said surface,l and an element tor forcing said tace against the abutment, and a pedal in operative relation with said shalts tor rocking the same. i

An automobile transmission mechanism con'iprising in combination, a transmission shalt and a gear thereon, a sun gear, planet- `ary gears meshing with said gears, a disc lixedto `rotate with the sungear, an arrestling abutinent at one side ol the disc and a movable plate `held against rotation at the other, a housing llange, a cam shalt interposed between .said liange` and plate and adapted topressthe `plate against the disc and the disc against the abutment, and a pedal on said cam shatti 4. An automobile transmission mechanism comprising in combination, a transmission shaft anda gear lined to rotate therewith;

two sun gears; planetary gears meshing with said; gears; and operative mechanism for :trictionally arresting each sun gear, automatically locking the sun gears together,

unlocking the sun gears, automatically hold- `means lor arresting one sun gear and clutch dis-cs fixed to rotate therewith; spring-actuated` clutch clamping elements lined to rotate with the othersun gear and adapted to igage the discs automatically; and `operative mechanism lor disengaging the elements, holding the elements normally disengaged, releasing the elements for ,automatic engagement, and arresting the elements.

6. in automobile transmission mechanism comprising in combination, a transmission shalt and a gear thereongftwo sun gears; planetary gears meshing with said gears; two discs lined to rotate with one sun gear; means tor arresting one disc; spring-pressed clamping elements lined to rotate with the other` sun gear and adapted to engage the other disc automatically; and operative mechanism tor disengaging the elements, automatically holding the elements disengaged, releasing the elements lor automatic engagement,and arresting the elements.

7. in automobile transmission mechanism comprising in combination, two operative sun gears, two discs lined to rotate with one gear, means lor arresting one disc, springactuated clamping elements lixed to rotate with the other gear and adapted to engage the other disc automatically, lrictional arresting means adjacent one clamping element, and means lor disengaging the clamping elements and forcing said element into engagement with the arresting means.

8. An automobile transmission mechanism comprisiirgI in combination, two operative sun gears and arresting means lor each, spring-pressed clutch clamping elements lined to rotate with one gear, a clutch disc element liXed to rotate with the other gear and adapted lor engagement with said elements, each clamping element including a ball thrust bearing, clutch disengaging cam shafts interposed between the bearings and adapted to roclzthereon for exerting equal pressures in opposite directions on the clamping elements against the spring resistance, 4arms on the cam shafts, and a pedal and equalizer in operative relation with said arms for rocking the cam shafts.

9.' An automobile transmission mechanism comprising in combination, two operative sun gears; means for arresting one gear and clutch discs iiXed to rotate therewith; springactuated clamping elements liXed to rotate with the other gear and adapted to engage the discs automatically; frictional arresting means adjacent one clamping element; and operative mechanism for rlisengaging the clamping elements, forcing said element into engagement with the arresting` means, and holding said element in a neutral position between thediscs and arresting' means.

10. An automobile transmission mechanism comprising in combination, two operative sun gears and arresting means for each; a clamping element having recesses carried by one gear; an aperture member sleeved to said element an adjustable clamping member splined to said element and screw-threaded to the apertured member; clutch springs pressing said element and apertured member adapted to lock the clamping member against change of adjustment; clamping discs splined to the clamping member; and clutch discs carried by the other gear and operatively arranged with said element, clamping member, and discs; said recesses registeringwith apertures of the apertured ieaoai member to facilitate turning thereof relative to said element tor adjusting the clamping member against the spring resistance.

ll. An automobile transmission mechanism comprising in combination, two operative sun gears and frictional arresting means for each, an operatively mounted seltengaging disc clutch for locking the gears together, clutch disengaging means including a pedal, seit' engaging pedal retaining means for holding the clutch normally disengaged, and an operatively related engine accelerator pedal At'or moving the retaining means to disengaging position.

12. An automobile transmission mechanism comprising in combination, a lmusing, two operative sun gears, a disc fixed to rotate with each gear, an arresting abutment for each disc having peripheral notches and a screw-threaded connection with said housing, means to facilitate turning of the abutments for adjusting purposes, and a locking lug removably secured in said housing `for engagement with said notches.

13. The combination with a pedal and cooperating mechanism adapted to ell'ect low speed in one position of the pedal and high speed in another position thereoit', of means for holding` the pedal in an intermediate neutral position, an operable engine accelerator, and means forming` an operative relation between the accelerator and holding means adapted to release the latter when the accelerator is operated.

In testimony whereof, I aiiix my signature.

VILLIAM C. SMITH. 

